Hydrogen-powered semi trucks with fuel cells on board have so far been mostly a future vision, but it remains a very viable concept.

Eighteen-wheelers are mostly powered by diesel, but until recently (as long as gas/diesel prices were high) liquefied natural gas (LNG) was an attractive, more affordable alternative, with compressed natural gas (CNG) for shorter hauls. But today, with natural gas price advantages gone, hydrogen may have an opportunity—particularly in markets served by CNG today. Ironically, because natural gas is hydrogen’s major feedstock, the still-low price for that fuel is what makes fuel-cell trucks a tantalizing possibility.

Flash back to 2011, when El Segundo, California-based Vision Motor Corporation provided a heavy-duty (Class 8) fuel-cell hauler to the Port of Long Beach, America’s second largest for cargo containers. With growing concern about diesel emissions from idling trucks waiting to be loaded, zero emissions from the “Tyrano” was a major advantage. The fuel cells on the truck kept its battery pack charged.

The Tyrano could reach 65 mph, with a fuel-cell output of up to 65 kilowatts, and 200-mile range. Refueling? A mere four to seven minutes. Vision claimed it could produce its tractors “at a competitive price to existing diesel and natural gas trucks.”

Then-Governor Arnold Schwarzenegger proclaimed the Tyrano “very exciting.” And the Los Angeles Times opined, “Experts said the venture could set the stage for a new era in green cargo movement.” Heather Tomley, director of environmental planning for the port, said of the 18-month $1 million pilot program, “We really want to see the truck put through its paces to see how durable the fuel-cell system is.”

Vision also announced that, working with Balqon Corporation, it intended to develop the Zero-TT, a fuel-cell/battery electric hybrid tractor for distribution centers, rail yards and marine terminals.

Now flash forward to late 2014, when Vision filed for bankruptcy, having been unable to make a profit. The company, despite impressive technology, had $1.3 million in assets, but $3.2 million in liabilities.

Despite this sad denouement, medium- and heavy-duty trucks powered by fuel cells are still an intriguing idea. California’s Air Resources Board (ARB) wrote a draft technology assessment on the concept late last year, and concluded, “Overall, fuel cells are a promising approach to enable zero- and near-zero emissions from the heaviest vehicle classes, including line haul trucks. Based on this assessment, ARB believes that fuel-cell technology will assist California in reaching its climate change, air quality and petroleum-dependence-reduction goals.”

ARB added that fuel cells “are the most promising advanced technology to enable long-haul trucks…to reach zero- or near-zero emission goals.” At the time, the agency noted some acceptance of commercial fuel-cell vehicles, especially forklifts. (By 2013, there were more than 4,000 of them in use, from companies such as Coca-Cola, Kimberly Clark, Whole Foods, FedEx and Sysco Foods.) Twenty fuel-cell transit buses were deployed as of last year, less than five shuttle buses, more than 35 delivery buses, and around 10 large but shorter-range “drayage” trucks.

The challenges? The fuel is more expensive than diesel. The cost of a large fuel-cell vehicle is still considerable (around $1.3 million for a 40-foot bus), though it has come down rather dramatically. Hydrogen tanks also take up more space, and weigh more, than conventional diesel tanks. Transit buses offer a somewhat better storage picture, since tanks can be located in the roof.

The best current opportunities for hydrogen trucks go along with a central refueling facility, which means returning to the depot at the end of a run (not cross-country hauls). Enterprises like that are run by Sunline Transit for its fuel-cell buses in Thousand Palms, California, and by AC Transit for its fleet in Emeryville, California.

Another fuel-cell truck pioneer is the Canadian Loop Energy company, which powers its vehicles with a hybrid fuel-cell/battery powertrain. President Ben Nyland says his trucks offers both purchase price and operating savings. “It actually costs enough less that we can compete directly with the incumbent technology being diesel and natural gas,” he said.

Nyland told the Vancouver Sun, “The emissions coming out of heavy-duty vehicles in cities are literally killing us. So there is a great opportunity in urban environments to replace polluting vehicles with zero-emission vehicles.” Loop is targeting the short- and regional-haul freight market, and it claims “a competitive total cost of ownership, without subsidies.”

Clearly, medium- and heavy-duty trucks powered by fuel cells show promise, but the combination of low gas prices, expensive development and the lack of a nationwide distribution system for hydrogen have slowed their adoption. But the exploding forklift market demonstrates that the right circumstances can lead to rapid commercial adoption.